Implement sourceAddId() & sourceRemoveId()

media/filters/chunk_demuxer.h

Index: media/filters/chunk_demuxer.h
diff --git a/media/filters/chunk_demuxer.h b/media/filters/chunk_demuxer.h
index ae690b912fc798d8070bd238587783ecca8b4a19..c61d5843dc22e1b12d0dfb98e91e07891e42f1b5 100644
--- a/media/filters/chunk_demuxer.h
+++ b/media/filters/chunk_demuxer.h
@@ -6,6 +6,7 @@
 #define MEDIA_FILTERS_CHUNK_DEMUXER_H_
 
 #include <list>
+#include <string>
 
 #include "base/synchronization/lock.h"
 #include "media/base/byte_queue.h"
@@ -22,6 +23,12 @@ class FFmpegURLProtocol;
 // from JavaScript to the media stack.
 class MEDIA_EXPORT ChunkDemuxer : public Demuxer, public StreamParserHost {
  public:
+  enum Status {
+    kOk,              // ID added w/o error.
+    kNotSupported,    // Type specified is not supported.
+    kReachedIdLimit,  // Reached ID limit. We can't handle any more IDs.
+  };
+
   explicit ChunkDemuxer(ChunkDemuxerClient* client);
   virtual ~ChunkDemuxer();
 
@@ -41,9 +48,22 @@ class MEDIA_EXPORT ChunkDemuxer : public Demuxer, public StreamParserHost {
   // Methods used by an external object to control this demuxer.
   void FlushData();
 
-  // Appends media data to the stream. Returns false if this method
-  // is called in an invalid state.
-  bool AppendData(const uint8* data, size_t length);
+  // Registers a new |id| to use for AppendData() calls. |type| indicates
+  // the MIME type for the data that we intend to append for this ID.
+  // kOk is returned if the demuxer has enough resources to support another ID
+  //    and supports the format indicated by |type|.
+  // kNotSupported is returned if |type| is not a supported format.
+  // kReachedIdLimit is returned if the demuxer cannot handle another ID right
+  //    now.
+  Status AddId(const std::string& id, const std::string& type);
+
+  // Removed an ID & associated resources that were previously added with
+  // AddId().
+  bool RemoveId(const std::string& id);

[scherkus (not reviewing), 2012/04/23 19:24:17]

what does true/false mean? could we have void?

is it CHECK-failable if you remove an ID that doesn't exist?

[acolwell GONE FROM CHROMIUM, 2012/04/23 22:15:23]

Yes we could have void. Eric wanted a bool returned in the WebKit code, "just in
case" we needed to signal an error. Since the WebKit call had a bool I figured
it made sense to pipe it all the way to here. I'll remove it and put the return
true in WebMediaPlayerImpl until we actually have a reason to plumb it all the
way to ChunkDemuxer.
Yes. Done

+
+  // Appends media data to the source buffer associated with |id|. Returns
+  // false if this method is called in an invalid state.
+  bool AppendData(const std::string& id, const uint8* data, size_t length);

[scherkus (not reviewing), 2012/04/23 19:24:17]

CHECK-fail instead?

[acolwell GONE FROM CHROMIUM, 2012/04/23 22:15:23]

No. It is possible for appends to happen when the ChunkDemuxer is in an error
state. We need to be able to return an error here. An error could have occurred,
but WebKit doesn't know about it yet.

   void EndOfStream(PipelineStatus status);
   bool HasEnded();
   void Shutdown();
@@ -95,6 +115,9 @@ class MEDIA_EXPORT ChunkDemuxer : public Demuxer, public StreamParserHost {
 
   ByteQueue byte_queue_;
 
+  // TODO(acolwell): Remove this when fixing http://crbug.com/122909 .

[scherkus (not reviewing), 2012/04/23 19:24:17]

nit: I'd just leave off that trailing period in this case :)

[acolwell GONE FROM CHROMIUM, 2012/04/23 22:15:23]

Done.

+  std::string source_id_;
+
   DISALLOW_COPY_AND_ASSIGN(ChunkDemuxer);
 };